Binding post construction

ABSTRACT

A post construction for looseleaf binders in which the post is comprised of two interengaging complementary parts, one for each cover. The two post parts are expanded by interior means to force them into tight engagement with the wall of a bore through the paper block and this operates to lock the binder. The post with its two parts assembled is generally tubular, and each part is made up of one or more sector shaped pieces of the tubular wall. The binding post parts can be formed integrally with their respective covers or they can be independent elements separate from the covers.

United States Patent Chamberlin Mar. 7, 1972 [54] BINDING POST CONSTRUCTION 1,552,147 9/1925 Hall ..85/ E [72] Inventor: John H. Chamberlin, 5070 West Lake FOREIGN PATENTS OR APPLICATONS Road, Cazenovia, NY. 13035 l 1,011,255 11 1965 Great Britain ..402 54 [221 1970 1,087,393 /1967 Great Britain ..85/84 [21] Appl. No.: 16,362

Primary Examiner-Jerome Schnall 52 us. Cl.... .....402/4s, 85/5, 85/84 Mama-3mm? Jenney [51] Int. Cl. .B42f 3/04, B42f 13/12 581 Field of Search ..402/46, 48-56; [57] ABSTRACT 5 E, 34 A post construction for looseleaf binders in which the post is comprised of two interengaging complementary parts, one for [56] References Clted each cover. The two post parts are expanded by interior means to force them into tight engagement with the wall of a UNITED STATES PATENTS bore through the paper block and this operates to lock the 1,339,197 5/1920 Hemingway ..85/84 binder. The post with its two parts assembled is generally tul,0l7,797 2/1912 Pitt 402/54 bular, and each part is made up of one or more sector shaped 851,096 Kfehbiel pieces of the tubular wall. The binding post parts can be 7" 9/1944 5 E X formed integrally with their respective covers or they can be 3,33 1,373 1 Lohme1er independent elements separate from the covers 831,773 9/ 1906 Copeland et al... ..402/49 953,298 3/1910 Schmidt ..85/4 UX 6 Claims, 8 Drawing Figures PATENTEUMAR 7 m2 IIIA INVEVI'OH. JOHN H CHAMBERLIN BINDING rosr CONSTRUCTION BACKGROUND OF THE INVENTION This invention relates generally to binders for loose leaves, and has particular reference to novel construction and arrangement for a post-type looseleaf binder.

Post-type binders, used principally when a large number of sheets are to be bound together in a single volume, frequently add undesired thickness to the volume by reason of projecting post heads, fastening elements or the like, This thickness, which is in addition to that of the paper block and cover members, is undesirable where storage space is at a premium, and projecting parts also have the disadvantage of increasing wear and tear on adjacent volumes. In many such binders, the post is comprised of telescoping members and when the binder is expanded there is a variation in the post diameter which permits a certain amount of page misalignment. Supplemental sleeves have been used to minimize this problem but this solution simply results in an additional unwanted part for each binding post.

In addition to the disadvantages noted above, the post binders of the prior art often have a complex structure that makes them relatively expensive to produce and difficult for the user to lock and unlock.

SUMMARY OF THE INVENTION The binding post of the present invention comprises a pair of complementary post parts which interfit in a nontelescopic manner such that the outside diameter of the post remains constant throughout its length, even when the binder is fully expanded. The post must operate in conjunction with a block of paper for the binding to lock, no provision having been made in the post construction for holding its interfitting parts in engagement with one another in the absence of the paper. Thus, the post with its two parts assembled has a hollow interior area in which means may be introduced for expanding the parts outwardly into tight engagement with the wall of a bore in the paper, whereby the binding is locked and the sheets of paper, posts and covers, if any, are securely bound together.

It is contemplated that the binding posts of the invention will be made of plastic and preferably, although not necessarily, that they will be molded as integral parts of the corresponding plastic cover members. In this manner, production can be simplified and the ultimate cost of the binders reduced. Molding the post parts integrally with the covers results in a post binder in which the binding structure is wholly contained within the combined thickness of the covers and paper block, there being no added structure on the outside of the covers to occupy extra space and cause wear on adjacent volumes. As will appear from the detailed description to follow, the binding post construction that is disclosed herein is also considerably easier to lock and unlock than the majority of the post bindings of the prior art.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is an exploded, perspective view of a post binder embodying the invention, with certain details of construction omitted;

FIG. 2 is an enlarged, fragmentary end elevation of a slightly modified form of the binder prior to assembly;

FIG. 3 is a right-side elevation, with parts shown in section of FIG. 2;

FIG. 4 is an elevation corresponding tothe lower part of FIG. 3 showing a modified post configuration;

FIG. 5 is an enlarged, fragmentary end elevation, with parts shown in section, of an assembled and locked post binder and paper block;

FIG. 6 is a horizontal section taken substantially on line 6- 6 of FIG. 5;

FIG. 7 is a section corresponding to FIG. 6 but showing a modified form of the post expansion means; and

FIG. 8 is an enlarged side elevation of a modified form of the post construction prior to assembly.

DESCRIPTION OF THE PREFERRED EMBODIMENTS With reference now to the drawings, FIGS. I-5 illustrate preferred embodiments of the invention wherein the parts of the binding post are formed integrally with the front and back covers I] and 12, each binding post 14 being comprised of a pair of interengageable, complementary parts 14a, 14b. While only two posts 14 are shown by way of example in FIG. I, it will be understood that three or more posts may be employed depending on the size of the binder.

The binding posts with their parts 14a, 14b assembled have an open central area 15 whereby the posts are generally tubular as indicated in FIGS. 6 and 7. Post part 14a has two diametrically opposed longitudinal sections of its wall removed, and the spaces 16a that are left by the removals are substantially equal in area to the remaining wall sections 17a. The spaces 16a and remaining wall sections 17a thus divide the post part 14a into quadrants in the illustrated embodiment of the invention. Post part 1412 is constructed in a similar manner with spaces 16b and wall sections 17!; of equal area dividing it into quadrants.

As shown in the drawings, the wall sections 170 of post part 14a are angularly displaced with respect to the wall sections 17b of post part 14b. This permits the wall sections I7a to be received in the spaces 16b of the post part 1412 and the wall sections 17b of the latter to be received in the spaces 16a of post part 14a, the parts engaging one another with a free sliding fit.

The posts 14, with their parts 14a and 14b engaged, have substantially cylindrical exteriors that are dimensioned so as to fit closely in the standard diametered bores provided in looseleaf paper. This is shown in FIG. 5 wherein one of the posts 14 is positioned inone of the bores 18 in a paper block or tablet 19. In accord with the invention, the binding is locked by causing each post to expand into tight frictional engagement with the wall of the paper bore in which it is positioned. More specifically, the four wall sections 17a, 17b are sprung outwardly by expansion means located in the open central area I5 of the post.

In FIGS. 2,5 and 6, the post expanding means is in the form of a pin or small rod 20 ofa diameter that is slightly larger than the diameter of the central opening 15 in the post. As shown in the drawings, the central opening extends through the covers with which the post parts are associated permitting the pins 20 to be pushed into position in the post interiors after the binding has been assembled with the paper block as shown in FIG. 5. As already indicated, the insertion of the larger diametered pins into the central openings 15 of the posts causes the wall sections 17a, 17b thereof to be forced outwardly into tight engagement with the wall of the paper block bore, FIGS. 5 and 6, so that the looseleaf sheets and covers are securely bound together. When it is desired to unlock the binding, the pins 20 can be pushed out of the post openings without difficulty by means ofa long slender instrument such as an awl or a nail.

FIG. 7 illustrates a modified form of expansion means in which a camming action is employed to effect the expansion of the binding posts. To this end, a camming element 21 in the form of an elongated block with a square cross section is positioned in the central opening 15 of each post 14. The camming element is provided with an end slot 22 and is adapted to be rotated within the post by a suitable key (not shown) that is inserted in the slot. Rotation of the camming element in the counterclockwise direction causes the longitudinal edges of the element to engage eccentric surfaces 24 on the post wall sections 17a, 17b and cam the latter outwardly into tight engagement with the wall of the paper block bore as described above in connection with FIG. 6. As shown in FIG. 7, the eccentric surfaces 24 follow a curve of uniformly decreasing radius and terminate at longitudinally extending shoulders 25.

As previously mentioned, the covers 11 and 12 and their associated post parts 14a and 14b are preferably molded plastic with each cover and its post parts being of unitary construction. In this connection, it can be seen from FIG. I that on the front cover II the wall sections 17a of the post part I411 are one above the other, or vertically oriented, while wall sections 17b of post part 14b are side-by-side or horizontally oriented. In order to enable the desired engagement with the back cover 12, its post parts are arranged in the opposite manner. However, if the back cover is turned top for bottom so that it is oriented in FIG. 1 like the front cover, it will be seen that the two are identical whereby but a single mold is required for both.

In FIGS. 1 and S, the covers 11 and 12 are relatively stiff and are provided with grooves 26 which form hinges where the covers can be folded back to expose the pages. In FIGS. 2 and 3, the covers 11 and 12' are more flexible and can simply be rolled back, without the need for hinges, as is indicated by the phantom lines 27. Like the covers 11 and 12, however, covers 11' and 12 can be molded integrally with their post parts 14a and 14b, the construction of the latter being the same. FIG. 4 shows a slightly modified post part 14a, the external cylindrical surface of which is formed with undulations or corrugations 28 for achieving greater frictional engagement with the wall of a paper block bore.

FIG. 8 illustrates a modification in which the mating post parts 29, 30 are not formed integrally with the covers but are independent thereof. Because of this, the parts are headed as at 31. While rounded heads are illustrated, fiat heads set into countersunk holes in the covers, so as to be flush therewith, are also contemplated. As in the embodiment disclosed in FIG. 2, the post of FIG. 8 is provided with expansion means in the form ofa pin 32.

It was noted at the outset that the nontelescopic engagement or interfitting of the post parts, as provided for by the invention, results in a post in which the outside diameter is constant throughout its length even when the binder is fully expanded. This prevents misalignment of the looseleaf sheets due to variations in the post diameter along its length. Referring to FIG. 6, it can be seen that if the opposite post wall sections 17b are removed, as by expanding the binder so that post parts 14a and 14b are no longer fully engaged, the remaining wall sections 17a still present the same effective overall diameter and will prevent any misalignment of the sheets. The latter is, of course, true by virtue of the fact that one-half of the post remains. In this connection, it will be understood that the number of wall sections and spaces making up the post parts is not critical so long as the two parts interfit and complement one another.

From the foregoing description it will be apparent that a novel and very useful binding post construction is provided by the invention, the resultant looseleaf binder being simple as to structure and operation, economical to produce, and efficient with respect to its space-saving ability. As will be understood by those familiar with the art, the invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof.

Iclaim:

I. In combination with a paper block having bores therethrough, binding posts for binding together the sheets of the block, each post comprising a pair of interengaging, complementary resilient parts, the parts of each post extending into one of said bores from opposite ends of the bore, the outer end of each part having enlarged means engaging the outer face of said block adjacent the bore, the post within a bore with its two parts assembled having a generally cylindrical exterior and a hollow interior formed by a longitudinal passage extending from end to end of the post and through each of said enlarged means and a separate expansion element having a diameter slightly larger than that of the passage, the expansion element beinginserted into the post passage to expand the resilient post parts and force them outwardly into tight engagement with the wall of the paper block bore in which the post is positioned, the expansion element being removable from the post passage by pushing it out either end thereof whereby the post parts are allowed to spring back into unexpanded position and can be removed from the paper block.

2. Structure as defined in claim 1 wherein the posts have a generally tubular cross section, and each part of a post comprises at least one sector shaped piece of the post tubular wall.

3. Structure as defined in claim 1 together with front and back covers for the paper block, the two parts of each post being respectively connected to the two covers.

4. In combination with a paper block and front and back covers on opposite sides of said block, the block and covers having bores adjacent one edge thereof; binding posts for binding together the sheets of the block and covers, each post comprising a pair of interengaging, complementary resilient parts connected respectively to the front and back covers, parts of each post extending into one of said bores from opposite ends of the bore, the post with its two parts assembled within a bore having a generally cylindrical exterior of substantially uniform diameter from end to end and a hollow interior formed by a longitudinal bore extending completely through the post and through each cover, and a separate expansion element having a diameter slightly larger than that of the post bore, the expansion element being inserted into the bore to expand the resilient post parts and force them outwardly into tight engagement with the wall of the paper block bore in which the post is positioned so that the sheets of the block and covers are bound together, the expansion element being removable from the post bore by pushing it out either end thereof whereby the post parts are allowed to spring back into unexpanded position and can be removed from the paper block.

5. A binding post assembly as defined in claim 4 wherein said postparts are formed integrally with their respective covers.

6. A binding post assembly as defined in claim 4 wherein the hollow posts have a generally tubular cross section, and each post part comprises a plurality of longitudinal sections of the post wall spaced from one another to receive therebetween the spaced longitudinal sections of its complementary post part. 

1. In combination with a paper block having bores therethrough, binding posts for binding together the sheets of the block, each post comprising a pair of interengaging, complementary resilient parts, the parts of each post extending into one of said bores from opposite ends of the bore, the outer end of each part having enlarged means engaging the outer face of said block adjacent the bore, the post within a bore with its two parts assembled having a generally cylindrical exterior and a hollow interior formed by a longitudinal passage extending from end to end of the post and through each of said enlarged means and a separate expansion element having a diameter slightly larger than that of the passage, the expansion element being inserted into the post passage to expand the resilient post parts and force them outwardly into tight engagement with the wall of the paper block bore in which the post is positioned, the expansion element being removable from the post passage by pushing it out either end thereof whereby the post parts are allowed to spring back into unexpanded position and can be removed from the paper block.
 2. Structure as defined in claim 1 wherein the posts have a generally tubular cross section, and each part of a post comprises at least one sector shaped piece of the post tubular wall.
 3. Structure as defined in claim 1 together with front and back covers for the paper block, the two parts of each post being respectively connected to the two covers.
 4. In combination with a paper block and front and back covers on opposite sides of said block, the block and covers having bores adjacent one edge thereof; binding posts for binding together the sheets of the block and covers, each post comprising a pair of interengaging, complementary resilient parts connected respectively to the front and back covers, parts of each post extending into one of said bores from opposite ends of the bore, the post with its two parts assembled within a bore having a generally cylindrical exterior of substantially uniform diameter from end to end and a hollow interior formed by a longitudinal bore extending completely through the post and through each cover, and a separate expansion element having a diameter slightly larger than that of the post bore, the expansion element being inserted into the bore to expand the resilient post parts and force them outwardly into tight engagement with the wall of the paper block bore in which the post is positioned so that the sheets of the block and covers are bound together, the expansion element being removable from the post bore by pushing it out either end thereof whereby the post parts are allowed to spring back into unexpanded position and can be removed from the paper block.
 5. A binding post assembly as defined in claim 4 wherein said post parts are formed integrally with their respective covers.
 6. A binding post assembly as defined in claim 4 wherein the hollow posts have a generally tubular cross section, and each post part comprises a plurality of longitudinal sections of the post wall spaced from one another to receive therebetween the spaced longitudinal sections of its complementary post part. 